Recent Advances in Gallium Phosphide Junction Devices for High-Temperature Electronic Applications

Recent advances in gallium phosphide technology are reviewed as they relate to high-temperature (T > 300°C) device applications. The electronic properties and materials aspects of GaP are summarized and compared to silicon and gallium arsenide. Minority-carrier unction devices are discussed as one area where this technology could have wide application. In this light, the high-temperature operation of two junction devices, a diode and a bipolar junction transistor (BJT), are displayed. The GaP diode is observed to provide excellent rectification properties with very low leakage over the full temperature range from 20°C to 400°C (< 3x10 -3A/cm2 at VR = 3 V, T = 400°C) and has demonstrated stable operation under bias for over 1000 h at 300°. The bipolar transistor has demonstrated constant current gain (6 < ß B < 10) and very low collector-base leakage for temperatures up to 450°C (ICO 80 µA at VCB = 3 V, T = 450°C). The contacting technology to GaP is identified as one area where additional work is necessary.